The two major categorizations of LLD are structural and functional. A third more minor category is environmental. In structural LLD there is an actual anatomical difference in the bones of the lower extremities where one side becomes shorter than the other. This type of LLD may be genetic, where the person is born in this way. In other cases it may be due to injury or infection through the growth phases of early childhood or adolescence. Some spinal abnormalities like scoliosis can also cause this condition. Functional LLD is where the bones are not the cause of difference but a muscle or pelvic condition has the effect of weakening the leg on one side. Conditions that can cause this are muscle inflexibility, adduction contractures and pelvic obliquity (amongst others). The third less severe category of environmental LLD is caused by discrepancies in the surface that the feet and legs are resting or walking on. Banked, uneven or curved surfaces can all cause environmental LLD. In LLD the asymmetric nature of the legs in relation to hips and back caused the centre of gravity to shift from its natural position. This then results in the body attempting to compensate by either tilting the pelvic areas towards the shorter side, increased knee flexing on the longer side, flexion of the ankle plantar and foot supination towards the shorter side.

Causes

Leg length discrepancies can be caused by poor alignment of the pelvis or simply because one leg is structurally longer than the other. Regardless of the reason, your body wants to be symmetrical and will do its best to compensate for the length difference. The greater the leg length difference, the earlier the symptoms will present themselves to the patient. Specific diagnoses that coincide with leg length discrepancy include: scoliosis, lumbar herniated discs, sacroiliitis, pelvic obiliquity, greater trochanteric bursitis, hip arthritis, piriformis syndrome, patellofemoral syndrome and foot pronation. Other potential causes could be due to an injury (such as a fracture), bone disease, bone tumors, congenital problems (present at birth) or from a neuromuscular problem.

Symptoms

Children whose limbs vary in length often experience difficulty using their arms or legs. They might have difficulty walking or using both arms to engage in everyday activities.

Diagnosis

The doctor carefully examines the child. He or she checks to be sure the legs are actually different lengths. This is because problems with the hip (such as a loose joint) or back (scoliosis) can make the child appear to have one shorter leg, even though the legs are the same length. An X-ray of the child?s legs is taken. During the X-ray, a long ruler is put in the image so an accurate measurement of each leg bone can be taken. If an underlying cause of the discrepancy is suspected, tests are done to rule it out.

Non Surgical Treatment

The non-surgical intervention is mainly usedfor the functional and environmental types of leg length discrepancies. It is also applied to the mild category of limb length inequality. Non-surgical intervention consists of stretching the muscles of the lower extremity. This is individually different, whereby the M. Tensor Fascia latae, the adductors, the hamstring muscles, M. piriformis and M. Iliopsoas are stretched. In this non-surgical intervention belongs also the use of shoe lifts. These shoe lifts consists of either a shoe insert (up to 10-20mm of correction), or building up the sole of the shoe on the shorter leg (up to 30-60mm of correction). This lift therapy should be implemented gradually in small increments. Several studies have examined the treatment of low back pain patients with LLD with shoe lifts. Gofton obtained good results: the patients experienced major or complete pain relief that lasted upon follow-up ranging from 3 to 11 years. Helliwell also observed patients whereby 44% experienced complete pain relief, and 45% had moderate or substantial pain relief. Friberg found that 157 (of 211) patients with LBP, treated with shoe lifts, were symprom-free after a mean follow-up of 18 months.

For discrepancies over five centimeters, more aggressive surgical procedures-specifically leg lengthening procedures-are typically required. The specifics of this operative procedure are beyond the scope of this informational page, but your child's physician will be able to discuss the details in reference to your child's specific problems when considered appropriate.